DE 10 2005 025 963 A1 teaches a device wherein the presence of a person on the vehicle seat is detected with the aid of optical sensors. The sensor signal is sent to an image-analyzing device. The detection of seat occupancy by a weight signal transmitted by a seat-occupancy sensor system is disclosed in DE 10 2006 005 047 B3. DE 20 2004 001 895 U1 discloses detecting the occupancy status of a vehicle seat using a detector mat to acquire information regarding a localized force on the seat. The known devices require the installation of additional expensive sensor equipment in the vehicle seat or in the interior of the vehicle. In contrast, the present invention provides a device that detects the occupancy status of a vehicle seat with low equipment expense and small space requirements.